When done together, these moves have serious strengthening benefits. They target practically every major muscle in your lower half.

Just like a regular squat, a squat jack is a lower body-centric move, relying heavily on the glutes, quads, hamstrings, and core, says Jenkins. The tweaked foot placement here—your feet are turned out at 45-degree angles, compared to a regular squat with both feet facing straight forward—“puts your legs in an abduction position,” explains Jenkins, which helps further target your glutes.

The second move—chair pose to reverse lunge—targets your lower body as well, focusing primarily on the glutes, quads, hamstrings, and core. The chair pose element in particular also targets your erector spinae (the muscles that line your spine), which helps promote good posture, adds Jenkins. Both the chair pose and the reverse lunge offer intense strengthening benefits, and these become even more potent when the two exercises are combined into one movement, as Jenkins recommends. Any time you combine multiple exercises to create a compound movement, you increase the number of muscle groups that have to work at once, making the whole exercise more intense. In this case, you're actually stringing together two already-compound exercises into one—that's no joke.

But, Jenkins says, this combo move is “especially great” if you have any issues doing lunges in general. Because each lunge, a single-leg movement, is separated by a chair pose, a double-leg movement, it’s a good progression for someone trying to build up the single-leg strength needed to master continuous lunges, Jenkins explains.

The plyometric element of the squat jacks provides additional strength and cardio benefits.

Plyometric moves in general (anything involving explosive movement, like hops and jumps) demand more from your muscles than non-plyometric exercises, explains Jenkins, in part because they require an intense burst of speed and power that's greater than what's required from your typical on-the-ground move. These explosive movements also drive the heart rate up, giving you a nice little burst of cardio work, too.

Because plyometrics involve jumping in the air and then landing back down, they can also help strengthen your joints—if done properly. This high-impact element means they—squat jacks, and any other plyometric movements—shouldn’t be performed with a high volume of reps. “Plyometrics are good to put in between strength training exercises,” says Jenkins, "but you don’t want to do a bunch of them back to back.” Staying within a range of 3 sets of 10 to 25 reps of plyometric moves in one day (that means total, if you combine all the plyo exercises you do) is a good, safe zone, she adds. If you have problems with your joints, it's a good idea to talk with your doctor before adding plyometrics into your routine.

The plyometric element in this specific move—the squat jack—also provides brief, yet welcome respite for your lower half. “Every time you explode [into the jump], you get a break while your body is in the air,” explains Jenkins.

Here’s how to do the moves:

Squat Jack

Stand with your feet wider than hip-distance apart and point your feet out away from your body about 45 degrees. Bend your arms at the elbows and clasp them together in front of your chest.

Keeping your weight in your heels, brace your core and squeeze your glutes as you sit back into a deep squat. Keep your chest lifted and your arms out in front to stabilize yourself.

Pause for a moment here and then jump up as high and as fast as you can, bringing your feet together, squeezing your glutes and core, and swinging your arms out to the sides.

Jump your legs back out and lower back down into the squat as you land, bringing your arms back to your chest. This is 1 rep.

Do 15 to 20 reps.

Make sure to keep your weight in your heels throughout the move, says Jenkins, as this will ensure glute activation. You also want to keep you chest up and your core tight to support and stabilize your spine. “If you’re not doing that, the pressure of the landing [from the jump] can hurt your joints,” she explains.

The depth of your squat will depend on your own range of motion, though as a general rule of thumb, Jenkins recommends bending your knees to a 90-degree angle or less. If the jumps are too much on your joints, just stick with a goblet squat (basically just the first two parts of the move) to get similar strengthening benefits, recommends Jenkins.

Chair Pose to Reverse Lunge

Stand with your feet hip-width apart. Bend your knees and push your glutes and hips back to sit back slowly, as if you were sitting into a chair.

Brace your core and keep your chest lifted. Extend your arms up and out in front of you, as if you are reaching toward the ceiling.

In this position, your weight should be shifted into your heels and your knees should track over your second toes (and not go beyond that point).

Hold this pose for eight deep breaths. Now you’re ready to begin the lunging sequence.

Keeping your glutes and hips pushed back and your arms raised, lift your left leg to step back about 2 feet into a reverse lunge.

Land on the ball of your left foot and keep your heel off the ground. Bend both knees to create two 90-degree angles with your legs.

In this positioning, your chest should be upright and your back completely flat. Your right shin should be perpendicular to the floor and your right knee should be stacked above your right ankle. Your butt and core should be engaged, and your arms extended straight in front of you.

Pause for a moment and then push through the heel of your right foot to return to the chair pose.

Pause for a moment in chair pose and then do a reverse lunge with the opposite leg, lifting your right leg to step back about 2 feet. Complete the reverse lunge as described above.

Pause for a moment and then press through the heel of your left foot to return to chair pose.

Continue doing reverse lunges, alternating your legs each time, with a chair pose in between each lunge, for 16 to 20 total reps (1 rep equals 1 reverse lunge plus 1 chair pose).

Although you’re technically combining two different exercises here, the sequence should be one slow, continuous movement, says Jenkins.

As you perform the movement, keep your chest up and straight. If your chest leans forward over your knees, then you’re putting your center of gravity forward, which will incorrectly place pressure on your knees and quads, explains Jenkins. Lastly, as with the previous move, keep your weight in your heels—in both feet for the chair pose, and in your front foot during the reverse lunge—to ensure glute activation.

For a quick lower-body circuit, do 3 sets of each move with the number of reps prescribed above. You can also get creative with how you incorporate these moves into your exercise routine, adds Jenkins. You can do them in between heavy weight training exercises, like leg presses, as a way to keep your heart rate up, or you can do them before, during, or after a run as a way to mix cardio with strength training (as Jenkins recommends in her Instagram Story). Just like with classic exercises, “there are all types of ways to mix it up,” she says.